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Question
In the circuit shown below, calculate the equivalent resistance between the points (i) A and B, (ii) C and D.
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Solution
(i) Between the points A and B : Three resistance 2 Ω, 2Ω, 2Ω are in series.
The equivalent resistance R' = 2 + 2 + 2 = 6 Ω
This is joined in parallel with a resistance 2Ω
The equivalent resistance R = `(2 xx 6)/(2 + 6) = 12/8 = 15. Omega`
(ii) Between the points C and D:
The above combination of equivalent resistance 1.5 Ω is in series with two resistances 2Ω and 2Ω
Total effective resistance between the points C and D is R
= 1.5 + 2 + 2 = 5.5
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